Vertical channel field effect transistors (VFET) generally provide significantly improved switching efficiency as compared to DMOS, UMOS, or other power devices. Particularly, the vertical channel field effect transistors made out of GaAs material have an on-resistance per unit area that is five to eight times lower than state of the art silicon DMOS or UMOS power devices. In addition, GaAs vertical channel field effect transistors have excellent switching speed, on the order of 1 to 2 nanoseconds.